The font library and the revivification display of characters are the important contents of the OS. Seeing as the number of the Chinese characters is big, the font library is the base of processing the Chinese information on OS. Using the font library, the Chinese characters could be displayed and imported.
There are three conventional font library technologies including bitmap font, vector font and outline font.
The advantages of bitmap font are that making and displaying of the bitmap font are easily, but it also has its disadvantages that it couldn't be magnified or reduced. That is the magnified and reduced effects are very poor. Besides when it was magnified the font capability would be square increased. Generally, an application need a plurality of fonts having various of sizes, its storage capability requirement is very huge. So that the bitmap fonts were used on the early OS or the embedded equipment that has lower requests on the characters display quality and number of characters.
The vector font library and the outline font library are popular on the OS at present, there are two types mostly, TrueType and Postscript. Now the most of PC Os use these two font libraries. The advantages are that these font technologies are mature, the font style is nice and it could be magnified and reduced, so that it can be used in the PCs. The disadvantages are that the structure of the font library is complex, the font revivification generator is complex, the effect of the small characters display is bad, the revivification speed of characters is slow, the capability of the font library is big and it could not meet the need of the embedded system. The font library technologies were both invented by America. We not only should pay much money, but also the development of our Chinese information processing would be baffled, it is abnormal that we are restricted on the Chinese characters font library technology area.
First of all, in the market there is no outline font library that could meet the need of the embedded system, because the memory capability of the embedded system is small. It will increase the cost while increase the memory capability. One typeface GB18030 of TrueType font takes 20 Mbyte storage space, and four typefaces take 80 Mbyte in total. At the present the advanced embedded system usually has only 16 Mbyte memory. The operating system itself cost some, applications need some, and the left is small and could not hold the huge outline Chinese font library. Many advanced PDAs and cell-phones could not be put in China market because they haven't been Chinese localized. As a result, they haven't found the way to meet the needs of the advanced Chinese embedded system.